What is Glucosamine Hydrochloride?

Glucosamine is an amino sugar that is produced naturally in humans. It is also found in seashells, or it can be made in the laboratory. Glucosamine hydrochloride is one of several forms of glucosamine.

It is important to read the labels of glucosamine products carefully since several different forms of glucosamine are sold as supplements. These products may contain glucosamine sulfate, glucosamine hydrochloride, or N-acetyl-glucosamine. These different chemicals have some similarities. But they may not have the same effects when taken as a dietary supplement. Most of the scientific research on glucosamine has been done using glucosamine sulfate. See the separate listing for glucosamine sulfate. The information on this page is about glucosamine hydrochloride.

Dietary supplements that contain glucosamine often contain additional ingredients. These additional ingredients are frequently chondroitin sulfate, MSM, or shark cartilage. Some people think these combinations work better than taking just glucosamine alone. So far, researchers have found no proof that combining the additional ingredients with glucosamine adds any benefit.

Products that contain glucosamine and glucosamine plus chondroitin vary a great deal. Some do not contain what the label claims. The difference can range from 25% to 115%. Some products in the US that are labeled glucosamine sulfate are actually glucosamine hydrochloride with added sulfate. This product will likely have different effects than one containing glucosamine sulfate.

Insufficient Evidence to Rate Effectiveness for...

Bone and joint disease called Kashin-Beck disease. Early evidence shows that taking glucosamine hydrochloride along with chondroitin sulfate reduces pain and improves physical function in adults with a bone and joint disorder called Kashin-Beck disease. The effects of glucosamine sulfate on symptoms of Kashin-Beck disease are mixed when the supplement is taken as a single agent.

Knee pain. There is some early evidence that glucosamine hydrochloride might provide some pain relief for people who have frequent knee pain as a result of joint injury.

Osteoarthritis. There is conflicting evidence about the effectiveness of glucosamine hydrochloride for osteoarthritis. Most of the evidence supporting the use of glucosamine hydrochloride comes from studies of a particular product (CosaminDS, Nutramax Laboratories). This product contains a combination of glucosamine hydrochloride, chondroitin sulfate, and manganese ascorbate. Some evidence suggests that this combination can improve pain in people with knee osteoarthritis. This combination might work better in people with mild-to-moderate osteoarthritis than in people with severe osteoarthritis. Another product (Gurukosamin & Kondoroichin, Suntory Wellness Ltd., Tokyo, Japan) containing glucosamine hydrochloride, chondroitin sulfate, and quercetin glycosides also seems to improve knee osteoarthritis symptoms.
The effects of taking glucosamine hydrochloride along with only chondroitin sulfate are mixed. Some evidence shows that taking a specific product (Droglican, Bioiberica S.A., Barcelona, Spain) containing glucosamine hydrochloride and chondroitin sulfate reduces pain in adults with knee osteoarthritis. However, other research shows that formulas containing glucosamine hydrochloride and chondroitin sulfate are not effective at reducing pain in patients with knee osteoarthritis.
Most research suggests that taking glucosamine hydrochloride alone does not reduce pain in people with osteoarthritis of the knee.
More research has been done on glucosamine sulfate (see separate listing) than on glucosamine hydrochloride. There is some thought that glucosamine sulfate may be more effective than glucosamine hydrochloride for osteoarthritis. Most research comparing the two forms of glucosamine showed no difference. However, some researchers have criticized the quality of some of these studies.

Rheumatoid arthritis. Early research shows that taking a specific glucosamine hydrochloride product (Rohto Pharmaceuticals Co.) in combination with prescription medical treatments reduces pain compared to a sugar pill. However, this product does not seem to decrease inflammation or reduce the number of painful or swollen joints.

Jaw pain (temporomandibular disorder). Early research shows that taking a combination of glucosamine hydrochloride, chondroitin sulfate, and calcium ascorbate twice daily reduces joint swelling and pain, as well as noise made at the jaw joint, in people with temporomandibular disorder.

How does Glucosamine Hydrochloride work?

Glucosamine in the body is used to make a "cushion" that surrounds the joints. In osteoarthritis, this cushion becomes thinner and stiff. Taking glucosamine hydrochloride as a supplement might help to supply the materials needed to rebuild the cushion.

Some researchers believe that glucosamine hydrochloride might not work as well as glucosamine sulfate. They think the "sulfate" part of glucosamine sulfate is the important factor because sulfate is needed by the body to produce cartilage.

Are there safety concerns?

Glucosamine hydrochloride is POSSIBLY SAFE for most adults when taken by mouth appropriately for up to 2 years. Glucosamine hydrochloride can cause gas, bloating, and cramps.

Some glucosamine products do not contain the labeled amount of glucosamine or contain excessive amounts of manganese. Ask your healthcare provider about reliable brands.

Special Precautions & Warnings:

Pregnancy and breast-feeding: There is not enough reliable information about the safety of taking glucosamine hydrochloride if you are pregnant or breast feeding. Stay on the safe side and avoid use.

Asthma: Glucosamine hydrochloride might make asthma worse. If you have asthma, use caution with glucosamine hydrochloride.

Diabetes: Some preliminary research suggests that glucosamine might raise blood sugar in people with diabetes. However, more reliable research indicates that glucosamine does not seem to significantly affect blood sugar control in people with type 2 diabetes. Glucosamine with routine blood sugar monitoring appears to be safe for most people with diabetes.

High cholesterol: There is some concern that glucosamine might cause cholesterol levels to increase in some people. Glucosamine might increase insulin levels. High insulin levels are associated with increased cholesterol levels. However, this effect has not been reported in humans. To be on the safe side, use glucosamine cautiously if you have high cholesterol levels.

High blood pressure: There is some concern that glucosamine might cause blood pressure to increase in some people. Glucosamine might increase insulin levels. High insulin levels are associated with increased blood pressure. However, this effect has not been reported in humans. To be on the safe side, use glucosamine cautiously if you have high blood pressure.

Shellfish allergy: There is some concern that glucosamine products might cause allergic reactions in people who are sensitive to shellfish. Glucosamine is produced from the shells of shrimp, lobster, and crabs. However, allergic reactions in people with shellfish allergy are caused by the meat of shellfish, not the shell. There are no reports of allergic reactions to glucosamine in people who are allergic to shellfish. There is also some information that people with shellfish allergy can safely take glucosamine products.

Surgery: Glucosamine hydrochloride might affect blood sugar levels and might interfere with blood sugar control during and after surgery. Stop using glucosamine hydrochloride at least 2 weeks before a scheduled surgery.

Are there any interactions with medications?

Warfarin (Coumadin) is used to slow blood clotting. There are several reports showing that taking glucosamine hydrochloride with or without chondroitin increases the effect of warfarin (Coumadin) on blood clotting. This can cause bruising and bleeding that can be serious. Don't take glucosamine hydrochloride if you are taking warfarin (Coumadin).

Medications for cancer (Antimitotic chemotherapy)Interaction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

Some medications for cancer work by decreasing how fast cancer cells can copy themselves. Some scientists think that glucosamine might increase how fast tumor cells can copy themselves. Taking glucosamine hydrochloride along with some medications for cancer might decrease the effectiveness of these medications.

There is some concern that taking glucosamine hydrochloride and acetaminophen (Tylenol, others) together might affect how well each works. However, more information is needed to know if this interaction is a big concern.

There has been concern that glucosamine hydrochloride might increase blood sugar in people with diabetes. There has also been concern that glucosamine hydrochloride might decrease how well medications used for diabetes work. However, research now indicates that glucosamine hydrochloride probably does not increase blood sugar in people with diabetes. Therefore, glucosamine hydrochloride probably does not interfere with diabetes medications. To be cautious, if you take glucosamine hydrochloride and have diabetes, monitor your blood sugar closely.

Dosing considerations for Glucosamine Hydrochloride.

The appropriate dose of glucosamine hydrochloride depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for glucosamine hydrochloride. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.